双三次插值C代码（利用opencv）

双三次插值C代码（利用opencv）

phasecubic2.cpp

D:文件及下载相关文档Visual Studio 2010Projectsphasecubic2phasecubic2

// phasecubic2.cpp : 定义控制台应用程序的入口点。
//
#include "stdafx.h"
#include <opencv2/opencv.hpp>
#include <opencv2/highgui/highgui.hpp>
#include <opencv2/imgproc/imgproc.hpp>
#include <string>
using namespace cv;
using namespace std;

int _tmain(int argc, _TCHAR* argv[])
{
    cv::Mat matSrc, matDst1, matDst2;
    matSrc = cv::imread("003.png", 2 | 4);
    matDst1 = cv::Mat(cv::Size(669, 431), matSrc.type(), cv::Scalar::all(0));
    matDst2 = cv::Mat(matDst1.size(), matSrc.type(), cv::Scalar::all(0));

    double scale_x = (double)matSrc.cols / matDst1.cols;
    double scale_y = (double)matSrc.rows / matDst1.rows;
    int iscale_x = cv::saturate_cast<int>(scale_x);
    int iscale_y = cv::saturate_cast<int>(scale_y);

    for (int j = 0; j < matDst1.rows; ++j)
    {
        float fy = (float)((j + 0.5) * scale_y - 0.5);
        int sy = cvFloor(fy);
        fy -= sy;
        sy = std::min(sy, matSrc.rows - 3);
        sy = std::max(1, sy);

        const float A = -0.75f;

        float coeffsY[4];
        coeffsY[0] = ((A*(fy + 1) - 5*A)*(fy + 1) + 8*A)*(fy + 1) - 4*A;
        coeffsY[1] = ((A + 2)*fy - (A + 3))*fy*fy + 1;
        coeffsY[2] = ((A + 2)*(1 - fy) - (A + 3))*(1 - fy)*(1 - fy) + 1;
        coeffsY[3] = 1.f - coeffsY[0] - coeffsY[1] - coeffsY[2];

        short cbufY[4];
        cbufY[0] = cv::saturate_cast<short>(coeffsY[0] * 2048);
        cbufY[1] = cv::saturate_cast<short>(coeffsY[1] * 2048);
        cbufY[2] = cv::saturate_cast<short>(coeffsY[2] * 2048);
        cbufY[3] = cv::saturate_cast<short>(coeffsY[3] * 2048);

        for (int i = 0; i < matDst1.cols; ++i)
        {
            float fx = (float)((i + 0.5) * scale_x - 0.5);
            int sx = cvFloor(fx);
            fx -= sx;

            if (sx < 1) {
                fx = 0, sx = 1;
            }
            if (sx >= matSrc.cols - 3) {
                fx = 0, sx = matSrc.cols - 3;
            }

            float coeffsX[4];
            coeffsX[0] = ((A*(fx + 1) - 5*A)*(fx + 1) + 8*A)*(fx + 1) - 4*A;
            coeffsX[1] = ((A + 2)*fx - (A + 3))*fx*fx + 1;
            coeffsX[2] = ((A + 2)*(1 - fx) - (A + 3))*(1 - fx)*(1 - fx) + 1;
            coeffsX[3] = 1.f - coeffsX[0] - coeffsX[1] - coeffsX[2];

            short cbufX[4];
            cbufX[0] = cv::saturate_cast<short>(coeffsX[0] * 2048);
            cbufX[1] = cv::saturate_cast<short>(coeffsX[1] * 2048);
            cbufX[2] = cv::saturate_cast<short>(coeffsX[2] * 2048);
            cbufX[3] = cv::saturate_cast<short>(coeffsX[3] * 2048);

            for (int k = 0; k < matSrc.channels(); ++k)
            {
                matDst1.at<cv::Vec3b>(j, i)[k] = 
                    abs(
                    (matSrc.at<cv::Vec3b>(sy-1, sx-1)[k] * cbufX[0] * cbufY[0] 
                    + matSrc.at<cv::Vec3b>(sy, sx-1)[k] * cbufX[0] * cbufY[1] 
                    + matSrc.at<cv::Vec3b>(sy+1, sx-1)[k] * cbufX[0] * cbufY[2] 
                    + matSrc.at<cv::Vec3b>(sy+2, sx-1)[k] * cbufX[0] * cbufY[3] 
                    + matSrc.at<cv::Vec3b>(sy-1, sx)[k] * cbufX[1] * cbufY[0] 
                    + matSrc.at<cv::Vec3b>(sy, sx)[k] * cbufX[1] * cbufY[1] 
                    + matSrc.at<cv::Vec3b>(sy+1, sx)[k] * cbufX[1] * cbufY[2] 
                    + matSrc.at<cv::Vec3b>(sy+2, sx)[k] * cbufX[1] * cbufY[3] 
                    + matSrc.at<cv::Vec3b>(sy-1, sx+1)[k] * cbufX[2] * cbufY[0] 
                    + matSrc.at<cv::Vec3b>(sy, sx+1)[k] * cbufX[2] * cbufY[1] 
                    + matSrc.at<cv::Vec3b>(sy+1, sx+1)[k] * cbufX[2] * cbufY[2] 
                    + matSrc.at<cv::Vec3b>(sy+2, sx+1)[k] * cbufX[2] * cbufY[3] 
                    + matSrc.at<cv::Vec3b>(sy-1, sx+2)[k] * cbufX[3] * cbufY[0] 
                    + matSrc.at<cv::Vec3b>(sy, sx+2)[k] * cbufX[3] * cbufY[1] 
                    + matSrc.at<cv::Vec3b>(sy+1, sx+2)[k] * cbufX[3] * cbufY[2] 
                    + matSrc.at<cv::Vec3b>(sy+2, sx+2)[k] * cbufX[3] * cbufY[3]
                    ) >> 22);
            }
        }
    }
    //cv::imwrite("cubic_1.jpg", matDst1);
    //cv::imwrite("cubic_2.jpg", matDst2);
    const char SrcWinNa[] = "SrcWindow"; 
    const char ResWinNa[] = "ResWindow";
    cvNamedWindow(SrcWinNa, CV_WINDOW_AUTOSIZE);
    imshow(SrcWinNa, matDst1);
    cv::resize(matSrc, matDst2, matDst1.size(), 0, 0, 4);
    cvNamedWindow(ResWinNa, CV_WINDOW_AUTOSIZE);
    imshow(ResWinNa, matDst2);
    cvWaitKey(0);
    return 1;
    //getchar();
    //return 0;
}